Electrical resistance



Dec. 4, 1928. 1,694,167

w. DUBILIER ELECTRICAL RES I STANCE Filed March 26, 1926 INVENTOR William Uubilier' HTTORNE Y Patented Dec. 4, 1928.

UNITED STATES PATENT OFFICE.

WILLIAM D'UBILIER, OF NEW ROCHELLE, NEW YORK, ASSIGNOR TO DUBILIER CON- DENSER CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

ELECTRICAL RESISTANCE.

Application filed March 26, 1926. Serial No. 96,098.

This invention relates to improvements in electrical resistances; especially resistances for radio apparatus.

An object of the invention is to provide an :electrical resistance, particularly a resistance of the type generally designated as ,a grid leak, with all the conductive parts thereof in permanent and eflicient contact, so that the resistance will operate to the best advantage, without impairing the action of the other radio appliances with which it must be connected.

The nature of the invention is set forth in. the following description and drawings, whichillustrate the best form of my invention now known to me; but the disclosure is illustrative only, and I may vary the details of construction without departing from the principle of the invention or exceeding the scope of the appended claims.

On the drawings, the view presented shows in section a. grid leak resistance according to my invention.

The numeral 1 indicates a tube or sleeve in which is a conductive resistance rod or element 2, which may be of insulation, such as glass for example, or any otherisuitabl-e material, covered with india ink or a film or envelope of some other substance having the properties required to give the rod low electric conductivity. The sleeve 1. has its extremities closed as usual' by conductive cups 3. To unite the endsof the rod or-stem 2 to the caps, so that the rod can be put into an electric radio circuit, I may snugly wrap each end of the rod 2 in thin piece or sheet metal, such as tinfoil 4, which I then tightly encircle by a metallic spiral 5, such as a. iece of spring or wire which binds the tinfoil upon .the rod 2. Then each extremity of the rod 2 is set in an embedment of solder 6. which fills and closes the ends of the sleeve 1. This solder 6 effectively connects and unites the ends of the rod 2 to the caps 3, and when conductors engage the caps 3, the resistance is put into circuit.

This method of forming the grid leak makes a permanent and secure union between the rod'and the caps 3 that are the terminals of the grid leak. Often in such a device a little looseness between the ends of the rod or resistance element 2 will give rise to noises in a radio set containing it, and the clearness of the reception is thus greatly reduced. To avoid such loosencss and prevent such noises the wrapping of tinfoil, encircled by the spiral spring 5, on each end of the rod 2 serves perfectly, and gives a 'springy to prevent the development of any looseness.

In some instances, I may use a piece in the shape of a strip of tinfoil 7, wrapped spirally on the end of the rod and held by the spring binding member 5 as indicated at the right of the tube 1. The construction of the grid leak may thus be slightly different at each end, as illustrated, or a rolled sheet 4, with spring 5, be used at both ends; or a spiral strip of tinfoil 7, with a spiral member 5 be used at both ends, as one may desire.

Having described my invention, what I believe to be new and desire to secure and protect by Letters Patent of the United States is 1. A resistance comprising an element with a piece of thin metal wrapped on its end, a spiral elastic binding member therefor, and a conductive embedment for the end of said element with said metal and said binding member.

2. A resistance comprising an element of low conductivity, and parts crumpled about the ends and elastic means in contact with said crumpled parts for providing a secure and eflicient connection of said element with an electric circuit.

3. A resistance comprising an element of low conductivity, a. metal sheet of foil wrapped on one end thereof, -a spiral yielding binding member forsaid sheet. and a conductive embedment for said end with said sheet and said member.

4. A resistance comprising an element of low conductivity, a strip of thin metal wound spirally on one end thereof, a spiral elastic binding member therefor, and a conductive embedment for said end with said strip and said member.

In test mony whereof I aflix my signature.

WILLIAM DUBILIER. 

